CN1916759B - Pressure impression die comprising cycloolefin copolymer - Google Patents

Abstract

A method is provided for transferring a pattern from a template (1) to an object (12) in an imprint process, using a two-step process. The first step includes contacting a pattern of the template surface with a polymer material comprising one or more Cyclic Olefin Copolymers (COCs), to produce a flexible polymer replica having a structured surface with an inverse of the pattern of the template surface. In a second step, after releasing the flexible polymer replica from the template, the inverse pattern of the flexible polymer replica is pressed into a resist layer on a substrate, to imprint a replica of the pattern of the template surface in therein.

Description

The imprint master that comprises cyclic olefine copolymer

Technical field

The present invention relates to the imprint lithography field, it comprises by the moldable layer on the target surface of the body structure surface of template or die and substrate is contacted, and pattern is transferred to the technology of substrate from template or die.More specifically, the present invention relates to be used for the polymer stamp of imprint process, it has makes described polymer stamp be suitable for the material property of this technology.The invention still further relates to two step process of making and using this polymer stamp.In this two step process, on flexible polymer foil, form the duplicate of die plate pattern by impression or injection molding, to obtain intermediate polymer stamp, then, polymer stamp was used for for second step, with imprinted pattern on the moldable layer that is applied to the substrate target surface.Particularly, the present invention relates to the polymer stamp made by the material that comprises one or more cyclic olefine copolymers (COC), and processing and utilize the technology of this polymer stamp.

Technical background

One of otherwise effective technique that is used to duplicate nano-architecture (that is, in 100nm level or littler structure) is millimicro imprint lithography (NIL).In the millimicro imprint lithography, the counter-rotating of the picture on surface of template copy (often being called die) is transferred on the object, and this object comprises substrate and is applied to the film (for example, polymeric material) of the moldable layer that often is called resist on it.After the suitable temperature more than the glass transition temperature that object is heated to thin polymer film, die is pressed to film, after the depth of pattern of expectation is transferred to film, then is the cooling of die and frees (often being called the demoulding).Perhaps, substrate is covered by photo anti-corrosion agent material, that is, radiosensitive polymkeric substance, it is crosslinked to make it carry out when ultraviolet radiation (UV) is exposed, and perhaps prepolymer cures becomes polymkeric substance when radiant exposure.This requires substrate or die is transparent to the radiation that applies.In the technology of carrying out subsequently after finishing impression, object (thin polymer film that comprises substrate and institute's composition) can carry out aftertreatment, that is, and and by the etching of the substrate in imprinting area, pattern transfer is arrived the target surface of substrate.

There are some difficulties that must consider in above-mentioned imprint process, so that finish the pattern transfer completely from template to the moldable layer that covers substrate.

If template and substrate are not to be made by identical materials, they normally are made from a variety of materials, and they generally have different thermal expansivity.This just means that during the heating and cooling of template and substrate, it is different with the degree of shrinking to expand.Even change in size is very little, also may be destroyed in imprint process, because the feature of the pattern that will be transferred is micron-sized, perhaps or even nano level.Therefore, the result is the fidelity that reduces duplicate.

Often use the die or the backing material of rigidity, when die is pressed to substrate, this will cause the air plankton between die and moldable layer, reduce the fidelity of duplicate equally.And during impression was handled, especially when die or substrate were not made up of flexible material, the granule foreign between die and moldable layer can cause the obvious damage of die or substrate.At the rigidity die during from the rigid substrate demoulding, also can cause physical damnification to die or substrate or both, after impression is handled, be difficult to substrate and comprise the template demoulding of pattern with high aspect ratio.In case the normally not reproducible use of die of damage.

The invention summary

The purpose of this invention is to provide and a kind ofly be used to improve imprint process, have the method that height duplicates fidelity, this method easily and be applicable to industry.

In order to realize this purpose, propose a kind ofly in imprint process, pattern to be transferred to method on the object from template, this method comprises two step process.In the first step, the template with patterned surface contacts with polymeric material, so that form the flexible polymer duplicate that has with template surface pattern opposite configuration surface.The flexible polymer duplicate of Xing Chenging is also referred to as intermediate polymer stamp at this like this, then, frees from template.In second step, as second template, it contacts with the plasticity surface of object, to impress the duplicate of its pattern in the plasticity body surface with the patterned surface of flexible polymer duplicate.This duplicate has such body structure surface, and it has the opposite polarity of intermediate polymer stamp pattern and the identical polar of primary template pattern.

Be used for normally high priced line of the template of imprint process or raw sheet, therefore, should make the wearing and tearing of template or damage minimum.Template can be made by any material, still, often by Si, Ni or other metal, or quartz makes, and randomly is provided with anti-sticking layer.On the other hand, the object that impress is often made by quite hard material, and such as silicon or other semiconductor material, it scribbles softer plasticity embossed layer.The step of impression object is a key point, and wherein under the condition of the outstanding structure that impresses, it is very important being arranged in parallel, and wishes the very little remnant layer of moldable layer, usually less than the 10nm level.Therefore, any not parallel layout or superpressure can cause the damage to template.By the two step stamped methods that propose, template only is used for the polymeric material softer than mould material, thereby makes the damage risk minimization.

Another key point in the imprint lithography is the demoulding or the step of freeing surface in contact.When the high price template is stamped in the final object, must avoid any one damaged among both.Owing to utilize two step process, can comprise two demoulding step, one of them is to make the polymer stamp of formation from the template demoulding, and optional another step is in the object demoulding of the polymer stamp of using subsequently from impression.As described below, can carry out for second step discretely by machinery, replace after second step, when polymer stamp still contacts with the object of impression, the dissolve polymer die.

Face the problem that the intermediate polymer stamp that is suitable for two step imprint process is provided and resemble following this method, find the intermediate polymer stamp advantageous particularly of making by the material that comprises one or more cyclic olefine copolymers (COC).Utilize that this material obtains excellent be in, polymer stamp has the good performance of freeing.More particularly, in first and second imprint step, the surface tension of this material or surface energy provide polymer stamp with the suitable performance of freeing.And the COC polymer stamp makes the UV that it is suitable in second imprint step assist imprint process to the UV optical transparency.

The polymer main chain that should be noted that the COC polymkeric substance all is made up of carbon and hydrogen, does not comprise any polar group, for example, and carbonyl, carboxyl, ether, ester etc.If do not have other polar group or present the group of chemical bonds to the non-localized electronic state of these main chains, the COC polymkeric substance is characterised in that, compares with tygon or polypropylene, has low-surface-energy.And the high band gap of main polymer chain causes UV transparent, and this makes this material be suitable for the auxiliary imprint process of UV.Certainly, specific COC derivant can synthesize, and to a certain extent, can obtain to contain substituent from the market, and it chemically is linked on the main polymer chain, so that increase surface energy and/or reduce band gap.These derivants can not be considered to the suitable candidate that will use in two step process described herein.

According to a preferred embodiment of the invention, first or initial step of processable polymer die is to utilize the template of Si or metal (such as nickel, titanium, zirconium, niobium, tantalum or aluminium) to carry out, and wherein preferably to be provided with surface tension be 18mN/m or littler anti-sticking layer to template.This anti-sticking layer for example obtains by individual layer (SAM) film of the Automatic Combined that is provided with on the stay in place form surface.Anti-sticking layer for example can comprise fluorinated alkyl phosphoric acid derivatives, fluorinated alkyl polyphosphoric acid derivative, PTFE or fluorinated alkyl silane.Combine with the COC polymeric material of the polymer stamp that is used for forming, obtain satisfied pick resistance, wherein polymer stamp have 28 and the 40mN/m scope in surface tension.

In second imprint step, when forming and the polymer stamp of the demoulding when being used for pattern transfer to substrate, material property also must coupling, especially, if polymer stamp is not mechanical stripping.Equally, for this reason, the polymer stamp that comprises COC produces splendid effect.By utilizing the COC derivant of surface tension for 28-40mN/m, preferably in the scope of 28-37mN/m, even it is preferred in the scope of 30-35mN/m, for example, might in surface tension is approximately the PMMA of 41 mN/m, impress, perhaps even more preferably UV crosslinkable or UV curable, have in the higher capillary material and impress.

Description of drawings

With reference to the accompanying drawings, embodiment of the present invention will be described in more detail, wherein:

Fig. 1 schematically represents according to present embodiment, by two step process of template to the processing duplicate of body surface;

Fig. 2 represents to use the method according to the embodiment of the invention, the AFM casting mode image of the linearity pattern that impresses in SU8;

Fig. 3 represents according to the embodiment of the invention, AFM casting pattern (tapping mode) image of the blue light that impresses in SU8 (BluRay) CD pattern;

Fig. 4 is provided by the SEM image by the column pattern with high aspect ratio micron-scale that provides according to embodiment of the invention impression;

The processing step of Fig. 5-7 diagram embodiment of the present invention;

Fig. 8 schematically shows embodiment of an apparatus according to the present invention, is used for carrying out in Fig. 1-3 or the common described technology of 5-7;

Fig. 9 schematically shows the equipment of Fig. 8, is loaded with polymer stamp and substrate in the initial step of handling.

Figure 10 pictorial image 8 and 9 equipment, with pattern when template is transferred to the processing step of work of substrate; With

Figure 11-13 is schematically illustrated in the molding process that uses in the first step of two step process according to embodiments of the present invention.

The detailed description of specific embodiments

The present invention relates to " two step imprint process " that are called at this.This term is understood that such technology, and wherein, in the first step, by imprint process or molding process, one or more duplicates of template that will have institute's patterned surface of nanometer and/or micron-scale are formed in one or more flexible polymer foil.The polymer foil of composition can be used as polymer stamp in second step.Perhaps, the polymer foil of composition is as die, and to form another impression on another polymer foil, it uses in second step subsequently.Like this, the first step of technology can produce two negative flexible polymer duplicates that pattern is opposite with the primary template pattern, the positive flexible polymer duplicate identical with the primary template pattern with pattern.In second step, formed duplicate can be used as flexible polymer stamp, impresses or the imprint process of two kinds of impressions copies to pattern on the body surface with the employing hot padding by carrying out subsequently, UV.

Term " millimicro imprint process " or " imprint process " are meant the technology of the copy protection of a kind of millimicro that is used to form template or die and/or micro-structure surface pattern as used herein, it be by die is pressed into moldable layer (such as, polymkeric substance or prepolymer) so that layer distortion and forming.This layer can be the film that separately applies on substrate or substrate end face, and wherein substrate can be different materials with layer.Perhaps, this layer can be a kind of part of single objects of material simply, and wherein this layer is defined as the part that is stretched over the certain depth of object volume from body surface downwards.During impression (hot pressing line) is handled, moldable layer can be heated to it more than glass transition temperature Tg, be cooled to subsequently below the described glass transition temperature, and/or during impression is handled or afterwards, polymkeric substance can be cured by means of the exposure of UV light or be crosslinked.The patterned surface of template and embossed layer has the structure of micron or nanometer range with regard to its degree of depth and width.

Term " duplicates fidelity " and is meant a kind of wherein copy protection of the printing mould structure of the anti-configuration on complete duplicate impression surface of formation.

In the research process in stamping technique field, the present invention finds that some performances of employed material in intermediate stamp and two good step imprint process are very important.Some performances of these materials are :-can roll performance by this material of thickness between 100 and 1000 microns for thin flexible foils.-paper tinsel distortion, or the performance that can produce the duplicate of die with millimicro and/or little patterned surface or template by injection molding from the granular or particle formed by this material by polymeric material is formed.

-material should have the 40mN/m of being lower than (or dynes/cm), and preferably less than 37mN/m, even less than the low-surface-energy of 35mN/m, certainly, surface energy should be higher than the surface energy of the template surface with anti-sticking layer, referring to following discussion.

-in second moulding process, material should not mix with the organic material that will impress (for example, polymkeric substance, oligomer and/or monomer material).

-material should have the glass temperature of the good definition between 100 and 250 ℃.

-material should have clear and definite light transmission: for the wavelength greater than 300nm is 80% transmissivity (method of testing ASTM:D1003).

Material should have other preferred properties:

-thermal linear expansion coefficient (CTE) 60-80 * 10-6m/ (mK) (method of testing: ASTM D696),

-less than 2% low molded shrinkage factor (method of testing: ASTM D955),

-pencil hardness between 3H and HB (method of testing: JIS K5401),

-refractive index: 1.4-1.6 and

The chemical resistance of-restriction or good a little anti-isopropyl alcohol, acetone and sulfuric acid.

Have been found that with the material group that conforms to of claiming be cyclic olefine copolymer (COC), based on a base polymer of cycloolefin monomers and ethene.This properties of materials is: high glass-transition temperature, high optical transparency, low contraction, low moisture absorption and low two indexs of refraction, and most of owing to big cycloalkene unit is linked on the main polymer chain at random or replacedly.For this reason, multipolymer becomes amorphism, and it has material to be suitable for the ideal performance of two step imprint process.Several business-like COC material based on different types of cyclic monomer and polymerization is arranged.For example, by the cyclic olefine copolymer that the Mitsui Chemicals America company limited of the Ticona GmbH of Germany or the U.S. is produced by means of the chain copolymerization of cyclic monomer and ethene, cyclic monomer all in this way 8,9,10-trinorbornene-2-alkene (norborene) or 1,2,3,4,4a, 5,8,8a-octahydro-1,4:5,8-dimethanonaphthalene (tetracyclododecen), its trade (brand) name is respectively the product of Topas and Apel.Replacedly, COC can buy from the Japan SYnthetic Rubber Co. Ltd of Japan and the Zeon Chemicals LP of the U.S., by means of the open loop displacement copolymerization of the various cyclic monomers after hydrogenation, obtains the product of trade mark Arton by name and Zeonex/Zeonor respectively.

The key character of considering is to use the surface energy or the surface tension of material.The molecule that is positioned at liquid is subjected to its attractive force (cohesion) of molecule on every side from all directions.When the distance of the separation spacing between molecule and the surface was enough big, these power compensated mutually.But when the separation spacing between molecule and the surface during less than the scope of its molecular force, the gravitation of acquisition is perpendicular to the surface towards liquid center.This phenomenon means that be necessary from liquid center's transportable molecule to its surperficial merit, perhaps in other words, compares with those molecules that are positioned at the center, and the molecule that is positioned near surface has higher potential energy.In order to increase the surface, molecule must move on to this surface, and the degree of the surperficial required merit of formation unit area is defined as surface energy, specific surface energy, or with mJ/m ²Or ergs/cm ²The surface energy of every area of measuring for unit.On the other hand, need mechanical force to increase the surface, because liquid attempts to make as far as possible its surface area to minimize.The power that acts on the edge on unit length surface at these edges is defined as surface tension, and with Newton meter ^-1(N/m), mN/m, or dynes cm ^-1Measure.Under the situation of liquid, term " specific surface energy " and " surface tension " are synonyms, are abbreviated as " σ " or " γ " usually.And given at this, surface tension level is illustrated in 25 ℃ value, and still, this value reduces along with the increase of temperature usually.

Equally, also need merit to form or to increase the surface to solid.Because blocks of solid can not divide naturally, for example, when forming the surface by splitting method, the interior energy of system must increase.The mode that is suitable for liquid is equally applicable to solid, and specific surface energy is defined as the constant of the ratio between the increase of interior energy of system and the surface area that its forms.Should also be noted that specific surface energy not only depends on the selection of material, and depend on for example configuration on surface.Minimum surface energy is represented the plane surface of the atomicity of zero defect monocrystalline.But here, the crystalline structure on surface changes with the block crystallization phase ratio that in most cases causes more coarse superlattice of formation, and its formation is for surface energy is minimized.

The surface of master module and the surface that forms the polymeric material of flexible polymer duplicate must have enough anti-cohesives and anti-stickiness energy each other, so as after to impress from template release polymers die, and do not damage the pattern of impression.And, in second step of flexible polymer duplicate material, must have enough pick resistance on anticorrosive additive material surface on the anti-substrate.

Because the energy minimization liquid that has than the low-surface-energy value is dispersed on the solid of high value usually.Under opposite situation, oppositely be correct.Therefore, between the good anti-cohesive between the different materials of the present invention and anti-stickiness can the surface energies at different materials, provide following relation:

σ _Solid(mould material)＜σ _Liquid(polymeric material) and

σ _Solid(polymeric material)＜σ _Liquid(anticorrosive additive material)

Here, mould material is meant the surfacing that contacts with polymeric material, and therefore, if anti-sticking layer is provided, it is meant the anti-sticking layer of template.Should also be noted that term " surface energy/tension force " is just correct in a vacuum material only.To the reason of reality, this term is through being usually used in the situation of solid-air, liquid-air interface.For the evaluation of the absolutely accurate of the wet performance of solid-liquid interface, must consider in addition " interfacial energy ", and the Young equation is represented equilibrium state:

σ _Solid-vacuum-σ _Solid-liquid=σ _{Liquid-vacuum}Cos ( ) (2)

Here, for desirable non-moistening or anti-adhesive properties, the contact angle between solid surface and the liquid surface

Must be between 90 ° and 180 °, it causes concerning σ _Solid-vacuum＜σ _Solid-liquidIn addition, in some cases, also must consider the dispersion part σ of surface energy _i ^d(describing nonpolar, long-range London force) and its polarity part σ _i ^p(describing polarity, the non-London force of short distance) is so that scrutinize the bond strength at interface.Yet, interfacial energy (σ _Solid-liquid) and σ _i ^dAnd σ _i ^pNormally ignorant, can think that the relation of equation (1) is suitable and is more useful approximate value, and σ _Solid(mould material) means the primary template of the anti-stick film of coating or the surface energy of die, σ _Liquid(polymeric material) means the surface energy of the flexible polymer foil of the temperature more than the glass temperature that is heated to it, σ _Solid(polymeric material) means the surface energy of the flexible polymer foil in finishing impression back solid phase, and σ _Liquid(anticorrosive additive material) means the surface energy of the anticorrosive additive material that deposits on substrate surface.

Have been found that COC polymeric material according to the present invention has the surface tension in the 28-40mN/m scope, cause having the significantly anti-stick performance of closing that it can be used ideally in imprint process of the present invention other material.Should be noted that not all COC has the surface tension in this scope.The COC that can buy on many markets is tested, by people such as J.Y.Shin at PureAppl.Chem., Vol.77, No.5, pp.801-814 is in the IUPAC technical report of 2005DIO:10.1351/pac200577050801 " chemical constitution of cyclic olefine copolymer and physical characteristics ".From the COC polymkeric substance of six kinds of tests, five kinds in the 28-40mN/m scope, two kinds in the 28-37mN/m scope, have only a kind of in the 30-35mN/m scope.Only consider anti-stick problem, COC satisfies the σ in the equation (1) in a big way _LiquidThe condition of (polymeric material), therefore, when master module has surface tension less than 20mN/m, typically when 18mN/m or littler scope, the resist layer that is coated to substrate is the scope at 45mN/m, is favourable to two step stamped methods described here then.For embodiment preferred, wherein template has the SAM anti-stick coating, make template have the surface tension of about 18mN/m, and have roughly that the crosslinked anticorrosive additive material of capillary UV (such as SU8) of 45mN/m is used for substrate, optimal surface tension for intermediate polymer stamp is about 31.5mN/m, or the scope of 30-33mN/m.

Here, term " flexible polymer foil " is meant flexibility, ductile and transparent polymer foil.According to the present invention, flexible polymer foil during composition or polymer stamp comprise cyclic olefine copolymer (COC).Preferably, polymer foil is evenly to be made by one or more COC, but in another embodiment, the material of polymer foil also comprises other compound.In preferred embodiments, polymer foil is made of one or more careful COC derivants of selecting, so that polymer foil has the surface tension in the 28-40mN/m scope.Preferred is in the scope of 28-37mN/m, 30-35mN/m even 30-33mN/m than close limit.

And, the polymer foil that the COC material forms is transparent to can be used for wavelength coverage crosslinked or the otherwise moldable layer of curing radiation line sensitivity, thereby in second imprint step, utilize polymer stamp when on substrate, impressing, can optionally use the auxiliary impression of radiation, can be opaque material to the radiation that can use wavelength coverage and the material of master module and substrate is provided.

Template is an element quite expensive on making, and can not repair or use repeatedly the template of damage once usually.Yet the method according to this invention, polymer stamp are easy to by quite cheap made, are preferably using twice or even only just can discard after once.Polymer stamp can or be freed from the substrate demoulding; thrown away then; perhaps when it still is bonded at the target surface of substrate, in bath with selected appropriate solution with the dissolve polymer die but be not dissolved in substrate or the lip-deep curable moldable layer of substrate target.

Because formed polymer stamp is as second template, impressing on the target surface of substrate, and substrate is not polymeric material usually, and the thermal expansivity of polymer stamp and substrate is obviously different.In order to overcome the above-mentioned defective that causes by this situation, according to the combination of auxiliary stamped method of the radiation in one embodiment of the invention and the auxiliary stamped method of heat, carry out second imprint step at least, wherein, polymer stamp is pressed in the moldable layer on the substrate.According to this method, the radiation-sensitive material as the moldable layer on the substrate and the step that polymer stamp and substrate are suppressed together, with the step of radiation irradiation (flooding) moldable layer and after the step of curing layer, and preferably also free pressure and, under the high constant temperature that keeps by attemperating unit, be favourable from the step of substrate demoulding polymer stamp.Attemperating unit generally comprises heater assembly and is used for the temperature controlling circuit of supply to obtain and to keep determining of balance heat, and also may comprise cooling device.

The embodiment of first or initial step of two step process is described referring now to Fig. 1 a-1f of accompanying drawing.The process of schematically illustrated initial step according to two different embodiments in Fig. 1.The process diagram of Fig. 1 a-1f is utilized the formation of the intermediate polymer stamp of hot padding.Yet will outline the another kind that forms polymer stamp below may technology.

Fig. 1 a illustrates template 1, and it is for example by silicon, nickel or other metal such as aluminium, quartz, perhaps in addition polymeric material form.Template 1 has the surface 2 of composition, and it comprises rib, groove, projection or the depression with micron or nano level height and width.Preferably, template surface 2 is provided with the anti-sticking layer that will describe.Template 1 and surface 2 be in the face of and contact the surface 4 of flexible polymer foil 3 and be provided with, flexible polymer foil 3 comprises or is evenly formed by the COC material.

By means of suitable method for stamping, as Fig. 1 b) shown in, the reverse pattern of template surface 2 is formed in the superficial layer on surface 4 of flexible polymer foil 3.Be placed on the position on the surface 4 that contacts polymer foil 3 at template surface 2 after, polymer foil is heated to the glass temperature T of COC polymkeric substance used in the paper tinsel _gMore than.When superficial layer reaches its glass transition temperature, exert pressure, so that template 1 and polymer foil 3 are suppressed together, the pattern of surface on 2 is stamped in the superficial layer on surface 4 of polymer foil 3.Utilization can be finished compacting by the hydraulic pressure or the air pressure of film supply by soft pressure technology, and this technology was explained in more detail with reference to second step according to the inventive method.Perhaps, can use more traditional hard pressure technology.Because the polymer stamp that forms in initial step is not final products, the depth of parallelism is not the key factor of initial step, and it is same going on foot for second.

In according to Fig. 1 hot NIL method a)-c), template 2 usefulness appropriate C OC layer of material covers are such as the Topas of U.S. Ticona company and the Zeonor of the Zeon company of Japan.Preferably after the end face of polymeric layer is provided with imprint membrane by vacuumize and heat the suction interlayer layout.When imprint temperature reaches moderate temperature, for example, be forced between the 20-80 crust at the liquid (but preferred gas) that film exists later.After pattern transfer, formed polymer stamp is from the master module demoulding.Good thermoplastic layer must have narrow process range (window), the high mechanical properties that it relates to imprint temperature, frees temperature and produce nanostructured, and nanostructured must be as the mould with aftertreatment.Heigh clarity to the UV radiation is very favorable.These performances obtain by the polymer foil of utilizing the COC material.

According to the concrete grammar that uses, promptly, the combination of the hot padding under constant temperature, UV impression or hot padding and UV impression, template 1 and the polymer foil 5 that is impressed can separate after the cooling or impressing processing after the cooling polymer paper tinsel just separate, this depends on selected material and its characteristic.After template 1 was freed from polymer foil 4, the polymer foil that impresses 5 (being also referred to as duplicate, shown in Fig. 1 c) had the pattern opposite or negative with the pattern of primary template 1 on its surface 4, can be used as flexible polymer stamp 5.

The schematically illustrated another kind of method that forms polymer stamp by injection molding of Figure 11-13.In Figure 11, first support component 120 is parallel to the body structure surface 2 of template 1 with stayed surface 121 and is provided with, and has the little midfeather 127 of the final average thickness that limits polymer stamp.Preferred polymers material 125 provides with particle or pellets, and by utilizing well heater 126 to melt in molten chamber 124, included well heater 126 is used for solid polymeric material is heated into the fusing form as a rule.Conduit 122 for example by the hole in the stayed surface 121 as shown in the figure from molten chamber 124 is directed at interval 127 between stayed surface 121 and the template surface 2.Another kind method, conduit can be from the guiding of the lateral parts between support component 120 and the template 1 interval 127.In addition, provide injection device 123, it can be used to the polymeric material of fusing is pressed in the interval 127 by conduit 122.Replacement is melt polymer in molten chamber 124, and polymeric material also can melt in its way by injection device 123 and conduit 122.

When support member 120 and preferably be contained in the second support member (not shown) template 1 when being provided with the close form of being arranged in parallel, as shown in figure 11, operation injection device 123 is with the polymkeric substance of injection fusing.In the embodiment of accompanying drawing, injection device 123 comprises with the driving of motor (not shown) with rotary screw, to such an extent as to the polymkeric substance of fusing is driven through conduit 122.As shown in figure 12, the polymkeric substance of fusing is pressed in the interval 127, to fill up the interval that forms depression on the template surface 2 that is included in composition.Template surface 2 usefulness cooling device (not shown) (such as the pipeline that is used for cooling fluid that is arranged on second support member that keeps template 1) control to the temperature that is lower than polymeric material 125 temperature of fusion.Like this, when the polymeric material of fusing extrudes rapidly when filling at interval 127, polymeric material passes through cooling curing.

Then, template 1 is freed from the cured polymer material, thereby forms the polymer stamp 5 with stamp surfaces 4, and it is the opposite duplicate of template surface 2, as shown in figure 13.Can free or the demoulding by any known technology.

According to the present invention, polymer stamp 5 both can be used for for second step, with with the pattern transfer of surface on 4 to target substrate, also can be used for other initial step, according to Fig. 1 d)-1f), make the second opposite duplicate 8 form another flexible polymer foil 6 with method similar to the above.The purpose that adopts another initial step in the back is to guarantee that the final pattern that forms in target substrate is opposite with the template surface pattern.In this embodiment, polymer foil 6 is to use its glass transition temperature and imprint temperature to be lower than the polymkeric substance composition of the temperature of flexible polymer stamp 5.And the composition surface 4 and 7 of polymer foil 6 and flexible polymer stamp 5 has anti-cohesive each other.In preferred embodiments, because the chemical property of the polymer foil of using, anti-cohesive just presents from beginning.And anti-cohesive is also strengthened by the deposition that comprises the anti-sticking layer of suitable release agent on one or two polymer surfaces.In addition, if polymer foil 6 should be carried out crosslinked after exposing radiation, at least must the transparent or replacedly enough radiation of transmission one of in the polymer foil 5 and 6 to the radiation that applies, crosslinked with the superficial layer that allows to realize paper tinsel 6, or if bulk can realize the crosslinked of whole paper tinsel 6.

It is opposite with first polymer stamp 5 and therefore identical with template 1 basically to form a kind of novel polymer die 8 its patterns, comprise the polymer stamp 5 that will have a patterned surface 4 towards and contact the surface 7 of second polymer foil 6.As mentioned above, second polymer foil 6 can be a bulk, or has the bearing bed that applies superficial layer on surface 7.In order to impress the pattern on surface 4 at the superficial layer of paper tinsel 6, if use the hot padding method, paper tinsel 6 is heated to more than the glass transition temperature of its superficial layer.As Fig. 1 e) shown in, then, exert pressure, so that first polymer stamp 5 is pressed in the superficial layer of polymer foil 6.After impressing, flexible polymer stamp 5 can mechanically be removed from polymer foil 6, that is, and usually after cooling polymer paper tinsel 8, perhaps another kind of method with suitable method, can chemically be dissolved whole die 5 or part die 5 by means of one or more suitable solvents.The result be new polymer stamp 8 its have surface 7 corresponding to the pattern of primary template 1.

According to the present invention, have with primary template 1 duplicate of being produced 5 or 8 opposite or the similar face pattern and will in second imprint step, be used as flexible polymer templates respectively, as at Fig. 1 g)-1i) left-hand side and right-hand side shown in.Here, surface 4 or 7 one of in the flexible polymer stamp 5 or 8 is arranged to contact with the surface 16 of object 12, object 12 comprises the substrate 13 with target surface 17 that the thin plasticity superficial layer 14 with radiation-sensitive materials (for example, by means of exposing radiation crosslinked prepolymer or polymkeric substance) covered.Because the material composition on surface, flexible polymer stamp 5 or 8 surface 4 or 7 surfaces 7 with respect to moldable layer 14 have anti-cohesive.By means of applied pressure, one of force in flexible polymer templates 5 or 8 and to suppress together, and polymer film 14 selected portions are applied exposing radiation with object 12, in moldable layer 14, form the opposite pattern of polymer stamp surface, shown in Fig. 1 h.The flexible polymer stamp 5 or the 8 pairs of radiation that apply are transparent or have minimum absorbability, so that the essential enough radiant quantity of transmission are to solidify or the material of crosslinked superficial layer 14 when exposing radiation.Impress and after cure after, as Fig. 1 h) shown in, flexible polymer stamp 5 or 8 can mechanically be removed from substrate 13, or another kind of method, chemically dissolve whole polymer stamp 5 or 8 or partial polymer die 5 or 8 by means of one or more suitable solvents with suitable method.

Fig. 1 i) is illustrated in and frees the impression object 12 that obtains behind flexible polymer stamp 5 or 8.For the pattern with transfer printing for good and all is fixed on the substrate, generally adopt further treatment step, to remove the thinnest part of residual film 14, to expose the target surface 17 of substrate, then, perhaps the etching target surface or with another kind of material covering it.Yet this actual detail of further handling is unimportant for the understanding of the present invention.

Fig. 1 is the quite simply expression according to the inventive method.Illustrated initial step can directly be utilized hot padding and carry out in block COC polymer foil on dotted line, or is undertaken by injection molding.If at step 1a)-1c) use hot padding, generally between template 1 (for example, can be nickel) and polymer foil 3, there be the poor of thermal expansion.Yet the elasticity of polymer foil 3 and the flexible polymer foil that guarantees are subjected to the thermal expansion that applies on the template 1 and stretch and shrink, and do not damage the pattern characteristics on the paper tinsel surface 4, and polymer foil 3 also has basically the thickness greater than the height of patterning.The thickness of polymer foil is generally in the scope of 50-500 μ m, and the height of patterning or the degree of depth are in the scope of 5nm-20 μ m, represent by following example.Though other size also is possible.

But second step of representing below the dotted line of Fig. 1 is preferably utilized the combination of heating and radiation and carries out.Its reason is, when impression is when carrying out on substrate, on the target surface of substrate, keep or residual superficial layer extremely thin usually, be several nanoscales.Therefore, it is normally destructive for fine structure that heating and cooling have the die and the polymkeric substance of the different a pair of interlayers that expand, and this will cause being tending towards peeling off fully.But, because according to the method for present embodiment, extruding, irradiation and after the step of curing all be under the constant temperature of control, to carry out, do not have the influence of thermal expansion.

Fig. 5-7 was shown schematically in according to embodiments of the present invention in second step, the base conditioning step of the transfer step of actual pattern or imprint step.These accompanying drawings are corresponding to Fig. 1 g)-1h) embodiment of left-hand side or the embodiment of right-hand side, but more detailed.Second imprint step can be pure hot padding method, that is, polymer stamp is pressed into and is heated in the above polymeric layer of its glass transition temperature, and then, and the cooling and the demoulding.Embodiment hereto, polymkeric substance must the careful materials of selecting relevant COC polymer stamp, and wherein the glass transition temperature Tg of substrate layer 14 must be lower than the glass transition temperature of COC.For example, polymer stamp can be used T _g=136 ℃ Zeonor ZF14 paper tinsel or use T _g=139 ℃ Zeonex E48R paper tinsel is made, and plasticity substrate layer 14 can be T _g=93 ℃ PWMA.Yet preferred embodiment is used by UV radiation-hardenable or crosslinked material as substrate layer 14.

Polymer stamp 10 shown in Figure 5, thereby corresponding to any of polymer stamp among Fig. 15 or 8.Polymer stamp 10 has the body structure surface 11 that will be transferred predetermined pattern, and it is corresponding to surface 4 or 7, and three-dimensional protrusion and be recessed to form height in the several mu m ranges of 1nm-and the characteristic dimension of width wherein may be littler, also may be bigger.The thickness of polymer stamp 10 is generally between 10-1000 μ m.Substrate 12 has target surface 17, and it is arranged essentially parallel to polymer stamp surface 11 and is provided with, and has midfeather in the starting stage between the surface, as shown in Figure 5.Substrate 12 comprises substrate base layer 13, and the pattern of polymer stamp surface 11 will be transferred on it.Although not shown, substrate also is included in the supporting layer below the substrate base layer 13.The pattern of polymer stamp 10 directly by at the impression-transfer of polymeric material in the process of substrate 12, described material can be used as superficial layer 14 and is applied directly on the substrate target surface 17.In another embodiment that dots, also adopt transfer printing layer 15, for example, second polymeric material.At US6, the example of this transfer printing layer has been described in 334,960, and they how to be used for imprinted pattern be transferred to substrate base layer 13 with aftertreatment.In the embodiment that comprises transfer printing layer 15, the upper surface or the outside surface of target surface 17 expression transfer printing layers 15, transfer printing layer 15 is arranged on the substrate surface of base 18 in order.

Substrate 12 is positioned at above the heating arrangement 20.Heating arrangement 20 preferably includes the heating main body 21 of metal (for example, aluminium).Heating element 22 is connected with heating main body 21 or is included in the heating main body 21, is used for giving heating main body 21 with thermal energy transfer.In one embodiment, heating element 22 is electric immersion heaters that insert the socket in the heating main body 21.In another embodiment, the electrical heating coil is arranged on heating main body 21 inside, or is connected to the lower surface of heating main body 21.In another embodiment, heating element 22 is a kind of passages that form in heating main body 21, is used to make add hot fluid by described passage.Heating element 22 also is provided with connector 23, is used to connect the extra power (not shown).Under electrically heated situation, connector 23 preferably is used to connect the electric current contact of power supply.For having the embodiment that is used for by the passage that adds hot fluid formation, described connector 23 preferably is used to be connected to the conduit of heated fluid source.Adding hot fluid for example can be water or oil.Also having another kind of the selection is to adopt the IR radiation heater as heating element 22, and it is designed to emitting infrared radiation on heating main body 21.In addition, temperature controller is included in heating arrangement 20 (not shown), and it comprises and heating element 22 is heated to selected temperature and maintains the temperature at device in the uniform temperature tolerance.Having known in this area has dissimilar temperature controllers, therefore is not described in detail.

The heating main body 21 preferably the cast metal (such as, aluminium, stainless steel or other metal) sheet.And, preferably using the main body 21 of certain mass and thickness, so that realize that at the upside of heating arrangement 20 heat evenly distributes, the upside of heating arrangement 20 connects substrate 12, is used for transferring heat to zone of heating 14 from main body 21 by substrate 12.For being used to impress 2.5 " impression of substrate handles, used thickness is at least 1cm (preferably at least 2 or 3cm), diameter is at least 2.5 " the heating main body 21 of (preferred 3 " or bigger).For being used to impress 6 " impression of substrate handles, used thickness is at least 2cm (preferably at least 3 or 4cm), diameter is at least 6 " the heating main body 21 of (preferred 7 " or bigger).Heating arrangement 20 preferably can be heated to 200-300 ℃ temperature at the most with heating main body 21, though lower temperature also is enough for most of technologies.

For the controlled cooling of layer 14 is provided, heating arrangement 20 also is provided with cooling element 24, and it is connected in the heating main body 21 or is included in the heating main body 21, is used for from heating main body 21 transferring heat energy.In preferred embodiments, cooling element 24 is included in a passage or a plurality of passage that forms in the heating main body 21, is used to make cooling fluid to pass through a described passage or a plurality of passage.Cooling element 24 also is provided with connector 25, is used to be connected to external refrigeration source (not shown).Preferably, described connector 25 is the conduits that are connected to cooling fluid source.Described cooling fluid is preferably water, still, also can be a kind of oil, for example, and insulating oil.

The thermoplastic-polymer solution material that the preferred embodiments of the invention are utilized radiation cross-linkable is as layer 14, but its preferably spin coating.These polymer solutions can also be that photochemistry strengthens.The example of this material is the mr-L6000.1XP of Micro Resist Technology, and it is that UV is crosslinkable.Another example of this radiation cross-linkable material is the negative photoresist material, as Shipley ma-N1400, SC100 and MicroChem SU8 one class.But the material of spin coating is favourable, because it provides the complete sum of entire substrate to apply accurately.

Another embodiment utilizes the material of the pre-polymerization of liquid or approximate liquid to be used as layer 14, and this material is by the radiation polymerizable.The example that is used as the available and spendable polymerizable material of layer 14 comprises Korea S 104-11Moonj I-Dong, Yusong-Cu, the NIP-K17 of the ZEN Photonics of Daejeon305-308, NIP-K22, and NIP-K28.The NIP-K17 principal ingredient is an acrylate, and 25 ℃ of viscosity with about 9.63cps.NIP-K22 also has the major component of acrylate, and its viscosity at 25 ℃ is about 5.85cps.These materials are at 12mW/cm ²Solidify under above 2 minutes the condition of ultraviolet radiation exposure.Another example that is used as the available and spendable polymerizable material of layer 14 is Berlin, Germany D-12555, the Ormocore of the Micro ResistTechnology GmbH of No. 325 211 mansions in Koepenicker street.This material has the unsaturated composition of inorganic and organic hybrid polymer thing of 1-3% photopolymerization initiating agent.Having the viscosity of 3-8mPas quite high at 25 ℃, is 365nm, 500mJ/cm at wavelength ²Under the condition of radiant exposure, fluid can be cured.Another kind of spendable material is at US6, record in 334,960.

The general character that all these materials and can be used for are implemented any other material of the present invention is that they are plastic, and when exposing radiation (particularly UV radiation), and for example, the curing of the crosslinked or prepolymer by the polymer solution material has ability to cure.They also have the surface tension greater than 40mN/m usually, and general about is 45mN/m or bigger.

When being deposited on substrate surface, according to using area, the thickness of layer 14 generally is 10nm-10 μ m.Curable or crosslinkable materials preferably is applied on the substrate 12 with liquid form, preferably uses spin coating, or optional use roller coat, dip-coating etc.Generally when using crosslinkable polymeric material, compare with quick (flash) method with the method for fractional steps of prior art, an advantage of the present invention is that polymeric material can carry out spin coating on entire substrate, and this provides the inhomogeneity favourable and method fast of good layer.Such as those crosslinkable materials of mentioning is solid at normal temperature generally, therefore, can use the substrate at high temperature precoating easily.On the other hand, the method for fractional steps and fast method must repeat (repeated) surface portion use repeated treatment, because this method can not be handled big surface in a step.This makes and the method for fractional steps and express method and the machine complexity that is used to implement this method at elapsed time aspect the cycle, and is difficult to control.

According to the preferred embodiments of the invention, the impression, by radiation curing embossed layer material and the back baked material treatment step be under constant temperature, to carry out.

The arrow of Fig. 5 represents that polymer stamp surface 11 is pressed into the surface 16 of plastic material layer 14.In this step, heating arrangement 20 is preferred for the temperature of key-course 14, to obtain the proper flow in the material of layer 14.Because the crosslinkable materials of layer 14, control heating arrangement 20, layer 14 is heated to the glass temperature T that surpasses layer 14 material _gTemperature T _pIn this article, T _pRepresent treatment temperature or imprint temperature, represent that it is impression, exposure and a public temperature levels of back baking step.Certainly, this constant temperature T _pLevel depends on layer 14 selected material type, because for the situation of crosslinkable materials, it must surpass glass transition temperature T _g, and cure after also being suitable for the layer radiation curing material.T to the irradiation crosslinkable materials _pGeneral in 20-250 ℃ scope, perhaps even in 50-250 ℃ the scope of being everlasting.For example, mr-L6000.1XP with 100-120 ℃ constant temperature whole impression, exposure and after carry out the test of success in curing.For the embodiment of utilizing radiation-curable pre-polymers, this material generally is liquid or approximate liquid in room temperature, therefore, needs to heat on a small quantity or do not heat to become the softness of enough impressions.Yet, these materials usually after exposure and before polymer stamp separation also must through after cure, be used to finish the sclerosis after the exposure.Therefore, in the imprint step that Fig. 5 step begins, treatment temperature T _pBe set to the temperature levels that cures after being suitable for.

How the structure that Fig. 6 illustrates polymer stamp surface 11 forms impression in material layer 14, material layer 14 is fluid forms or is flexible form at least that wherein fluid is forced to fill up the depression of polymer stamp surface 11.In illustrated embodiment, the highest projection in the polymer stamp surface 11 does not penetrate downwards up to substrate surface 17.This avoids damaging for protection substrate surface 17 is favourable, particularly for polymer stamp surface 11.Yet in another embodiment, such as the situation that comprises transfer printing layer, impression can proceed to transfer printing layer 17 downwards always.In the embodiment shown in Fig. 5-7, polymer stamp is made by the COC material, and the COC material is to can be used for solidifying the predetermined wavelength of selected plastic material or the radiation 19 of wavelength coverage is transparent.For the polymer stamp of utilizing above-mentioned radiation to form, the retaining layer that wherein is preferably formed the sensitive surface layer of pattern also is transparent to the UV radiation, or replacedly, retaining layer is very thin, so that its UV absorbs low to being enough to that the radiation of q.s is passed through.Generally be pressed into layer 14, when between polymer stamp 10 and substrate 12, having suitable arrangement, applied radiation 19 in polymer stamp 10.When being exposed to this radiation 19, the curing of plastic material begins, and the shape that presents for the curing of solid body 14 ' depends on polymer stamp 10.In layer 14 was exposed to step process under the radiation, well heater 20 was by temperature controller control, with the temperature that keeps layer 14 in temperature T _p

After being exposed to radiation, carry out the back baking step, with the material of complete hardened layer 14 '.In this step, heating arrangement 20 is used for providing heat to layer 14 ', with polymer stamp 10 with bake layer 14 ' before substrate 12 separates, to the sclerosis main body.And, by keeping said temperature T _pBake after carrying out.Like this, polymer stamp 10 and material layer 14,14 ' from the curing materials 14 by being exposed to radiation begin keep uniform temp after finishing, to cure, and separating randomly by polymer stamp 10 and substrate 12.Like this, eliminated owing to be used for the accuracy limitations that any material coefficient of thermal expansion difference of substrate and polymer stamp is caused.

Polymer stamp 10 for example is to take out by peeling off with the method for drawing, as shown in Figure 7, owing to select to make this method to simplify according to COC material of the present invention.Formation and cured polymer layer 14 ' are retained on the substrate 12.Here, no longer go through the various different modes of the further processing of substrate and its layer 14 ',, also do not depend on how to realize this further processing because the present invention neither relates to this further processing.In general, be used for the pattern transfer of polymer stamp 10 for example can be comprised the then etching or the plating of strip step to the further processing of substrate base layer 13.

Fig. 8 schematically illustrates a preferred embodiment according to equipment of the present invention, also can be used for implementing the embodiment of the method according to this invention.Should be noted that this accompanying drawing is schematically purely, is used to illustrate the different characteristic of this equipment.Particularly, the size of different characteristic is not on common specifications.This equipment is particularly useful to implementing second step of the present invention, and still, it is good too to be used to implement initial step.

Equipment 100 comprises first major part 101 and second major part 102.In illustrated preferred embodiment, these major parts are that first major part 101 is arranged on above second major part, have scalable interval 103 between described major part.When carrying out surface imprint by the method shown in Fig. 5-7, template and substrate are very important at the correct aligning of side direction (being commonly referred to as X-Y plane).If impression is to carry out near the pattern top layer of the prior existence of substrate or its, this is a particular importance.Yet,, certainly, when needs, to combine with the present invention at this different modes of not being devoted to the particular problem of aiming at and overcoming these problems.

First (top) major part 101 has ventricumbent surperficial 104, the second (bottom) major part 102 and has supine surperficial 105.Supine surperficial 105 is smooth basically, the part that perhaps has substantially flat, surface 105 is arranged on dull and stereotyped 106 or forms a part of dull and stereotyped 106, and dull and stereotyped 106 play the effect that impression is handled the supporting construction of the template of usefulness or substrate, and this will 9 and 10 more at large describe in conjunction with the accompanying drawings.Heating main body 21 is placed on a part that contacts with dull and stereotyped 106 or form flat board 106.Heating main body 21 forms the part of heating arrangement 20, and comprises heating element 22, and preferably also comprises cooling element 24, shown in Fig. 5-7.Heating element 22 is connected to the energy 26 by connector 23, for example, and a kind of power supply with current control device.And cooling element 24 is connected to cooling source 27 by connector 25, for example, a kind of have be used to control flowing and the cooling fluid reservoir and the pump of temperature controlling device of cooling fluid.

In illustrated embodiment, being used to adjust at interval, 103 device is to provide by be provided with the piston piece 107 that is connected to flat board 106 in its outer end.Piston piece 107 is connected to column 108 movably, and it preferably is maintained fixed with respect to first major part 101.Shown in the arrow among the figure, being used to adjust at interval, 103 device is designed to by being substantially perpendicular to basic plane surface 105 (promptly, along the Z direction) move and second major part 102 is moved to more close first major part 101, or further from first major part 101.Moving can be manually finishing, but preferably by means of adopting hydraulic pressure or pneumatic shuttle.Illustrated embodiment can change with many modes in this respect, for example, replaces near dull and stereotyped 106 column that are connected to the fixed piston spare.The mobile loading and unloading that are mainly used in that should also be noted that second major part 102 have the equipment 100 of template and substrate and are used for equipment is arranged on the initialization position.But, preferably in actual moulding process, not comprising moving of second major part 102, embodiment will be described below so as shown.

First major part 101 comprises the peripheral seal 108 around surface 104.Preferably, seal 108 is ring seals, such as O shape ring, still, alternatively can be made up of the several interconnection seals that form sealing 108 continuously together.Seal 108 is arranged in the recess 109 of surperficial 104 outsides, and preferably can be from described recess dismounting.In illustrated embodiment, this equipment also comprises the radiation source 110 of 104 back, surface that are arranged on first major part 101.Radiation source 110 can be connected to radiation source driver 111, and it preferably includes power supply or is connected to the power supply (not shown).Radiation source driver 111 can be included in the equipment 100, but or outside web member.In abutting connection with the surface portion 112 on the surface 104 that radiation source 110 is provided with is by being that material transparent is formed to the certain wavelength of radiation source 110 or the radiation of wavelength coverage.Like this, from radiation source 110 radiation emitted by described surperficial position 112, towards interval 103 transmissions between first major part 101 and second major part 102.The surface portion 112 that plays window role can be formed by the fused silica of easily having bought, quartz or sapphire.

An embodiment according to equipment 100 of the present invention also comprises mechanical clamp, is used for substrate and die (not shown) are clipped together.Particularly, in the embodiment with the external alignment system that was used for before pattern transfer aiming at substrate and die, in the time of must being sent in the Embosser comprising the aligning stack of laminations of die and substrate, mechanical gripping means is preferred.

At work, equipment 100 also is provided with flexible partition 113, and it is smooth basically and engages seal 108.In preferred embodiments, flexible partition 113 is and 108 separable of seals, and only by applying opposite pressure from dull and stereotyped 106 surface 105 and engaging with seal 108, this will explain below.Yet in another embodiment, barrier film 113 for example sticks with glue agent or by being that an integral part of seal 108 is connected to seal 108.And in this replaceable embodiment, barrier film 113 can join on the major part 101 securely, and seal 108 is arranged on the outside of barrier film 113.For such as an illustrated embodiment, same, barrier film 113 is that using the certain wavelength of radiation source 110 or the radiation of wavelength coverage is that material transparent forms.Like this, be transmitted to the interval 103 by described cavity 115 and its interface wall 104 and 113 from radiation source 110 radiation emitted, for the embodiment of Fig. 7-9, the example that can be used for the material of film 113 comprises polycarbonate, polypropylene, tygon, PDMS and PEEK.The thickness of barrier film 113 generally is 10-500 μ m.

Equipment 100 preferably also comprises the device that is used for providing vacuum between die and substrate, so that before passing through UV radiation hardening layer, from the moldable layer suction air impurity of lamination interlayer.This in Fig. 8 with vacuum pump 117 as an example, vacuum pump 117 usefulness conduits 118 be connected to unobstructedly surperficial 105 and barrier film 113 between the interval in.

Form conduit 114 in first main part 101, be used to make the space of fluid media (medium) (gas, liquid or gel) by being limited by surface 104, seal 108 and barrier film 113, this space is as the cavity 115 of described fluid media (medium).Conduit 114 can be connected to pressure source 116 (such as, pump), and it can be the external part or the built-in part of equipment 100.Pressure source 116 is designed to provide adjustable pressure (particularly superpressure) to contained fluid media (medium) in described cavity 115.Be suitable for the using gases pressure medium such as illustrated embodiment.Preferably, described medium is selected from air, nitrogen, argon gas.If replace the use liquid medium, preferably to have the barrier film that is connected to seal 108.This liquid can be hydraulic oil.Another kind of possibility is to use gel as described medium.

Fig. 9 illustrates the equipment embodiment of the Fig. 8 when being loaded with the substrate 12 that is used for photoetching treatment and polymer stamp 10.In order to understand this accompanying drawing better, also with reference to accompanying drawing 5-7.Second major part 102 moves down from first major part 101, is used to open interval 103.The illustrated embodiment of Fig. 8 is illustrated in a kind of equipment that substrate 12 end faces are equipped with transparent polymer die 10.Substrate 12 is arranged on its back side on the surface 105 of heating main body 21, and heating main body 21 is arranged on second major part 102 or in second major part 102.Therefore, substrate 12 has its target surface 17 towards last polymerizable material (for example, UV crosslinkable polymer solution) layer 14.For simplicity, as seen all features of heating arrangement 20 do not illustrate in Fig. 9 in Fig. 5-7.Polymer stamp 10 is arranged on the substrate 12 or near the substrate 12, its body structure surface 11 is towards substrate 12.Can be provided for aiming at the device of polymer stamp 10 and substrate 12, but in this schematic accompanying drawing, not illustrate.Then, barrier film 113 is arranged on the end face of polymer stamp 10.Be connected to the embodiment of first major part for its septation 113, certainly, in fact need not on polymer stamp, to be provided with the step of barrier film 113.For the sake of clarity polymer stamp 10, substrate 12 and barrier film 113 are to illustrate fully dividually in Fig. 9, and they are layered on the surface 105 in actual conditions.

The working position of Figure 10 devices illustrated 100.Second major part 102 has risen to its septation 113 and has been sandwiched in seal 108 and the surface position between 105.In fact, polymer stamp 10 and substrate 12 are all extremely thin, the several of millimeter branch are generally only arranged, and the actual flexion of barrier film 113 are extremely small as shown in the figure.Also have, surface 105 is provided with the peripheral position of raising in the position by barrier film 113 contact seals 108, is used to compensate the combination thickness of polymer stamp 10 and substrate 12.

In case major part 101 and 102 engages to clamp barrier film 113, cavity 115 is sealed.Suction by vacuum pump 117 applies vacuum, with the superficial layer suction air impurity from substrate 12.Then, pressure source 116 is designed for provides superpressure to the fluid media (medium) in the cavity 115 (it can be gas, liquid or gel).Pressure in the cavity 115 is delivered to polymer stamp 10 by barrier film 113, and polymer stamp 10 is pressed to substrate 12, with the polymer stamp pattern in the embossed layer 14, consults Fig. 6.Crosslinkable polymer solution generally needs preheating, to overcome its glass transition temperature T _g, this glass transition temperature T _gBe about 60 ℃.The example of this polymkeric substance is above-mentioned mr-L6000.1XP.When using this polymkeric substance, the equipment 100 with combination radiation and heating efficiency is particularly useful.Yet, for these two kinds of materials, need the back baking step usually, with sclerosis radiation curing layer 14 '.Therefore, as mentioned above, an aspect of of the present present invention is the temperature T that the material of layer 14 is provided raising _p, this temperature is higher than the situation of crosslinkable materials, and be suitable for the radiant exposure material after cure.Start heating arrangement 20 with zone of heating 14, until reaching T by means of heating main body 21 by substrate 12 _pT _pActual value depend on the material of selecting to be used for layer 14 certainly.For example, mr-L6000.1XP according to the molecular weight distribution in the material, can use the temperature T in 50-150 ℃ of scope _pThen, the pressure medium in cavity 115 increases the crust to 5-500, the favourable crust to 5-200, the preferred 20-100 crust of increasing.Polymer stamp 10 and the corresponding pressure of substrate 12 usefulness are forced together.Because flexible barrier film 113 obtains the absolute of power and evenly distributes on the whole surface in contact between substrate and the polymer stamp.Thereby making polymer stamp and substrate itself relative to each other is that absolute parallel ground is provided with, and has eliminated any irregular influence in the surface of substrate or polymer stamp.

When polymer stamp 10 and substrate 12 combine by the fluid medium pressure that applies, trigger radiation source with emitted radiation 19.Radiation has seen through the surperficial position 112 of window role, sees through cavity 115, barrier film 113 and polymer stamp 10 and transmission.Radiant section ground or be absorbed in fully in the layer 14, thus layer 14 material provides by the barrier film by pressure and auxiliary compression, crosslinked in being arranged in parallel fully between polymer stamp 10 and substrate 12 or solidify and solidify.The radiant exposure time is depended on material type and the amount in the layer 14, the radiation wavelength that combines with material type, and radiation power.The feature of solidifying this polymerizable material is known equally, and the correlation combiner of above-mentioned parameter is known to one skilled in the art equally.In case fluid solidifies cambium layer 14 ', further exposure does not have big influence.Yet if cure with cured layer after needing fully, after exposure, the material of layer 14 ' can be at predetermined constant temperature T _pUnder cure or cure firmly the certain hour cycle after carrying out, for example, 1-10 minute.For example, to the public treatment temperature T of mr-L6000.1XP example at 100-200 ℃ _pAfter cure and generally carried out preferably approximately 3 minutes 1-10 minute.For SU8, the time of exposing radiation, wherein the scope of 3-5 second was successfully tested between 1 and 10 second, then, and at about 70 ℃ T _pCure 30-60 second after carrying out.

According to equipment 100 of the present invention, after to cure be to carry out in marking press 100, this just means and does not need the substrate extraction device and be put in the stove separately.Save a treatment step like this, it makes may save time and cost in impression is handled.Because when carrying out the back baking step, polymer stamp 10 still remains on constant temperature T _p, and also have the pressure of selecting towards substrate 10 potentially, and the structure plan that obtains also reaches degree of precision in layer 14, feasiblely like this might form good structure.Next be the compression, the exposure and after cure, reduce the pressure in cavity 15, and two major parts 101 and 102 be separated from each other.After this, substrate separates with polymer stamp, further handles according to the prior known technology of imprint lithography.

First pattern of the present invention comprises the silicon substrate 12 with layer 14 covering of the NIP-K17 of thickness 1 μ m.After the pressure by barrier film 113 usefulness 5-100 crust compresses about 30 seconds, open radiation source 110.Radiation source 110 generally is designed to launch at least the following ultraviolet radiation scope of 400nm.In preferred embodiments, adopt the emission spectrum scope to cool off xenon lamp as radiation source 110 at the air of 200-1000nm.Preferred xenon type radiation source 110 provides 1-10W/cm ²Radiation, and be designed to take place the pulse of flash of light 1-5 μ s with the pulse rate of 1-5 pulse per second.104 form quartz window 112 on the surface, are used to by radiation.Time shutter preferably in 1-30 second, is used for fluid layer 14 is aggregated into solid layer 14 ', and still, the time shutter can be up to 2 minutes.

Use about 1.8W/cm ²By 200-1000nm integrate, time shutter of 1 minute carried out the test of mr-L6000.1XP.In this article, should be noted that employed radiation will wavelength coverage be limited within the wavelength coverage that makes polymer cure that is applied in the layer 14, certainly, also be transmitted in radiation outside this scope from employed radiation source.Under the constant process temperature successfully exposure and in succession after cure after, second major part 102 drops to the position similar to Fig. 9, subsequently, slave unit takes out template 10 and substrate 12 separately and further to handle.

Because it is constant that in fact term constant temperature means, keeps certain temperature even mean the design temperature controller, the actual temperature that obtains has fluctuation in certain limit inevitably.The stability of constant temperature depends primarily on the precision of temperature controller and the inertia of whole device.And, should be appreciated that even the method according to this invention can be used for impressing the split hair structure that reaches 1 nanometer, as long as template is not too big, temperature variation a little can not have a significant impact.Suppose that the structure at the template periphery has width x, reasonably the space tolerance is the mark of above-mentioned width, and such as y=x/10, y becomes the parameter of design temperature tolerance so.In fact, applying template and backing material thermal expansivity separately, the size of template (generally being radius) and space tolerance parameter y can calculate the effect difference in the thermal expansion easily.From this calculating, suitable temperature tolerance that can the accounting temperature controller, and the machine that is applied to handle.

With shown in Figure 1, the advantage of application flexibility polymer foil comprises following several respects in " two steps " stamped method as mentioned above:

Because the different heat expansion coefficient of the die of using in stamped method and the backing material of use, the flexible characteristic of employed polymer foil alleviates the complicacy of pattern transfer.Therefore, this technology provides the possibility of pattern transferring between the surface of material that with the different heat expansion coefficient is characteristic.Yet most polymer features of using in application are that (general range is 60 and 70 * 10 for very close thermal expansivity ^-6C ^-1Between) make the easier processing of impression between two kinds of different polymer foil (shown in Fig. 1 e).

In polymer foil (having composition or non-patterned surface) with another object (for example, be coated with the substrate of polymer film, the template that perhaps comprises silicon, nickel, quartz or polymeric material) in the moulding process between, the flexibility of employed polymer foil and extension characteristics prevent the snotter of air.If when paper tinsel one of was pressed in these objects shown in Fig. 1 b, 1e, 1h, the polymer foil role was identical with barrier film, exactly air is pressed onto the edge of imprinting area from the center of imprinting area, wherein air can leave imprinting area.

Because degree of flexibility at employed polymer foil particle between polymer foil and the template or between the object of its pressurization, and the obvious surfaceness of template or object, no matter one of in polymer foil or the object that comprises at Fig. 1 b), 1e) and 1h) shown in the moulding process, can prevent obvious damage.

Because employed COC polymer foil is to for example high transparent of UV radiation, even when using opaque template and substrate, also can use the UV curable polymer in above-mentioned moulding process.

The low surface tension of COC polymer foil falls between the surface tension of the surface tension of SAM template anti-sticking layer and many anticorrosive additive materials (the particularly crosslinkable negative resist of UV), makes it can use them ideally in two step stamped methods.As a rule, need on the low surface tension polymkeric substance, not deposit anti-sticking layer in addition and make said method simply and industrial use.Clearly say, may in anti-stick material, form the polymer replication die.

If the material behavior of the different polymeric materials of using in method (for example, glass transition temperature, optical transparence and the curability behind exposing radiation) mutual coupling, described and be very suitable for producing just (pattern is identical with primary template) and bear the duplicate of (pattern and primary template are opposite) above then in the method shown in Fig. 1.

Employed flexible polymer stamp anti-aging and resistance to wearing makes its application flexibility polymer stamp repeatedly in second step of stamped method.Replacedly, polymer stamp is only used once, then they is thrown away.In any case this all improves the life-span of primary template 1, because primary template 1 never must be used for hard and non-flexible material are impressed.

The flexibility of employed polymer foil and extension performance make inflexibility die or substrate be easy to the demoulding from flexible foils, reduce the physical damnification on die or substrate.

After impressing, replace the mechanical stripping of polymer foil from substrate, replacedly, make polymer foil can be by means of suitable solvent chemical dissolution.Have in transfer printing under the situation of pattern of high aspect ratio (that is, the degree of depth of patterning is in fact greater than its width), mechanical stripping meeting damage substrate or die, said procedure is preferred.

Not only at the pattern on primary template surface, and the physical size of primary template can easily be transferred in the polymer foil.In some applications, the layout of the pattern on final substrate is crucial.For example, should be replicated the hard drive pattern and the center of aligning dish.Here, master die can be produced with center pit.After impression, the concave-convex of center pit is formed in the flexible polymer foil, and it can be used for the pattern on the paper tinsel is aimed at the dish that finally duplicates.

The duplicate that produces on polymer flake can reach the development method of novel class, and it can not carry out the commonsense method of nickel and nickel plating.Here, the polymer flake of impression for example at first combines with rigid substrate by the auxiliary method for stamping of UV.After this, this thin slice metallizes with crystal grain layer and electroplates, to hold the nickel copy of original template.Many other transform methods through described invention are intelligible.

Embodiment

As master module, use the metal form of being furnished with the SAM anti-sticking layer.Template is preferably made by nickel, although other embodiments for example can be made by vanadium, aluminium, tantalum, niobium, zirconium or titanium.Anti-sticking layer comprises fluorinated alkyl phosphoric acid derivatives or fluorinated alkyl poly-phosphate derivative, and it comprises phosphorus atoms and alkyl chain.This anti-sticking layer how to form with and the details that how is provided with at template surface on the books in WO2005/119360, therefore, this document is listed in as a reference at this.As the replacement of this anti-sticking layer, can use the layer that comprises silane family, phosphate group and carboxyl family.The embodiment of this anti-sticking layer is on the books in WO2004/000567, and it is also listed in as a reference at this.

The number of C OC polymer foil of having used is:

The Topas8007 of Germany Ticona GmBH: glass temperature is 80 ℃ a thermoplastic random copolymer.Topas is only transparent to the above wavelength of about 300nm, and is characterised in that low surface tension.Can obtain the paper tinsel that thickness is 50-500 μ m, use the thick paper tinsel of 130-140 μ m here.

The Zeonor ZF14 of Japan Zeon Chemicals: glass temperature is 136 ℃ and is 92% thermoplastic polymer to the optical transmission rate of the above wavelength of 300nm.The paper tinsel that uses has the thickness of 188 μ m, and, can obtain the other thickness of 50-500 mu m range.

The Zeonex E48R of Japan Zeon Chemicals: glass temperature is 139 ℃ and is 92% thermoplastic polymer to the transmissivity of the above wavelength light of 300nm.The paper tinsel that uses has the thickness of 75 μ m.

The surface tension of these materials or energy are general in the scope of 30-37mN/m.

The anticorrosive additive material that was successfully used to for second step is the SU8 of U.S. MicroChem Corp., and it is a kind of photo anti-corrosion agent material, and the light of wavelength exposure back is curable between to 350nm and 400nm.SU8 has the surface tension of about 45mN/m.Between SU8 film and silicon substrate, use the thin LOR0.7 film of a kind of U.S. MicroChem Corp. as adhesion promoters.

Embodiment 1

The surface has a kind of live width and is 80nm, highly continues to be impressed among the Zeonor ZF14 in 3 minutes under 150 ℃ and 50 crust for the nickel template of the line pattern of 90nm.The Ni surface to obtain to be lower than the low surface tension of 20mN/m, preferably is lower than 18mN/m with fluoridizing the pre-service of SAM anti-sticking layer.The Zeonor paper tinsel is mechanically removed from template surface, neither damages the pattern of template, does not also damage the pattern of duplicate.The Zeonor paper tinsel is as new template, and it is stamped in the thick SU8 film of 100nm.The SU8 film is to be spun on the 20nm LOR film that is spun in advance on the silicon substrate, and in order to improve the pick resistance between SU8 film and the Zeonor paper tinsel, handle with other coating on the neither one surface.Under 70 ℃ and 50 crust, continue to impress in 3 minutes.The SU8 film exposed for 4 seconds to UV light by optical clear Zeonor paper tinsel, and cured clock more than 2 minutes.In whole moulding process, it is constant that temperature and pressure keeps, respectively at 70 ℃ and 50 crust.Freeing temperature is 70 ℃, can mechanically remove from the SU8 film at this temperature Zeonor paper tinsel, neither damages the pattern of polymer template paper tinsel, does not also damage the pattern of duplicate film.Fig. 2 is illustrated in the afm image of the impression that obtains in the SU8 film that deposits on the silicon wafer, and silicon wafer is processed with said method, still, does not have anti-sticking layer on the Ni die.However, the COC polymer stamp can be duplicated good pattern in the middle of explanation utilized on evidence.

Embodiment 2

Utilize and same procedure and the identical parameters described in example 1, it is that 100nm and width are that the nickel template (by the AFM development) of the BluRay pattern of 150nm is stamped among the Zeonor ZF14 that the surface is had structure height.The Zeonor paper tinsel is as new template, and it is stamped in the thick SU8 film of 100nm.Equally, here use and same procedure and the identical parameters in example 1, described.The afm image of the impression that obtains in the SU8 film that deposits on silicon wafer is shown in Figure 3.

Embodiment 3

Use the surface to comprise the nickel template of micron pattern of the high aspect ratio of 1-28 scope.The characteristic dimension scope highly is 17 μ m from 600nm-12 μ m.Before impression, this surface is covered by the anti-stick film of phosphate base.The nickel template is impressed in the polycarbonate paper tinsel under 190 ℃ and 50 are clung to and continues 3 minutes.In order to improve the pick resistance between Ni template and the polycarbonate membrane, handle with other coating on the surface of polycarbonate paper tinsel.Freeing temperature is 130 ℃, and polycarbonate foil can mechanically be removed from nickel surface under this temperature, neither damages the pattern of template, does not also damage the pattern of duplicate.Polycarbonate foil is used as new template to impress to the Topes paper tinsel.Be stamped under the pressure of 120 ℃ temperature and 50bar and carried out 3 minutes.Handle with other coating on the neither one surface, and purpose is the pick resistance that improves between polycarbonate and the Tope paper tinsel.Freeing temperature is 70 ℃, and Topas can mechanically remove from the polycarbonate paper tinsel under this temperature, neither damages the pattern of template paper tinsel, does not also damage the pattern of duplicate paper tinsel.Then, the Topas paper tinsel is as new template, and it is stamped into thick being spun in the SU8 film on the silicon substrate of 6000nm.Equally, in order to improve the pick resistance between SU8 film and the Topas paper tinsel, handle with other coating on the neither one surface.70 ℃ and 50 the crust under continue 3 minutes impression.The SU8 film exposed for 4 seconds to UV light by optically transparent Topas paper tinsel, and did not change 70 ℃ temperature and cure clock more than 2 minutes, and perhaps pressure is 50 crust in the entire process process.Freeing temperature is 70 ℃.Then, the Topas paper tinsel dissolved 1 hour in 60 ℃ p-dimethylbenzene fully.The SEM image that obtains is shown in Figure 4.

Experimental

Utilize the different disposal parameter, carry out method for stamping given in the above-mentioned example, in some cases, cover with the anti-stick film of phosphate base with the Ni die of isomorphic graphs not.Before rotation LOR and SU8 film, directly use isopropyl alcohol and acetone rinsing and clean substrate (2-6 inch silicon wafer).The die size of using is the 2-6 inch.The Obducat6 inch NIL equipment that utilization is furnished with the UV module impresses.

After impressing, by means of the NanoScope IIIa microscope that comes from digital implementation (Digital Instruments), finish the atomic force microscopy (AFM) in the casting pattern, to detect imprint result and die.

Utilize Obducat CamScan MX2600 microscope under 25kV, to finish scanning electron microscopy (SEM).

The present invention who relates to two step stamped methods briefly and by concrete detailed embodiment has been described in the front, wherein at first forms the polymer stamp of COC material, uses then.In claims, limit claimed scope.

Claims (28)

1. polymer stamp that is used for imprint process, it comprises the flexible polymer foil on the surface that has thereon the structure plan that is formed by the original impression in the imprint process last time, wherein said polymer foil is to be made by the material that comprises one or more cyclic olefine copolymers (COC), wherein, the surface energy that is heated to the flexible polymer foil of the above temperature of its glass transition temperature is higher than the surface energy of the original impression that applies anti-stick film; And the surface energy of the flexible polymer foil in finishing impression back solid phase is lower than the surface energy of the anticorrosive additive material that deposits on substrate surface, wherein impresses the imprinted pattern through transfer printing in the anticorrosive additive material that deposits on described substrate surface.

2. polymer stamp as claimed in claim 1, wherein the COC polymer foil have 28 and 40mN/m between surface tension.

3. polymer stamp as claimed in claim 1, wherein the COC polymer foil have 28 and 37mN/m between surface tension.

4. polymer stamp as claimed in claim 1, wherein the COC polymer foil have 30 and 35mN/m between surface tension.

5. polymer stamp as claimed in claim 1, wherein the COC polymer foil has the thickness of 50 μ m-1mm.

6. polymer stamp as claimed in claim 1, wherein the COC polymer foil has the thickness of 75 μ m-250 μ m.

7. polymer stamp as claimed in claim 1, wherein the COC polymer foil has the glass transition temperature between 100 ℃ and 250 ℃.

8. polymer stamp as claimed in claim 1, wherein the COC polymeric material is based on the multipolymer of cyclic monomer and ethene.

9. polymer stamp as claimed in claim 8, wherein the COC polymeric material is based on: 8,9,10-trinorbornene-2-alkene (norborene) or 1,2,3,4,4a, 5,8,8a-octahydro-1,4:5, the multipolymer of 8-dimethanonaphthalene (tetracyclododecen) and ethene.

10. the application of a moldable polymer composition, described moldable polymer composition comprises the composition of one or more cyclic olefine copolymers (COC) as flexible polymer foil, described polymer foil has thereon the surface of the structure plan that is formed by the original impression in the imprint process last time with the die as imprint process, wherein, the surface energy that is heated to the flexible polymer foil of the above temperature of its glass transition temperature is higher than the surface energy of the original impression that applies anti-stick film; And the surface energy of the flexible polymer foil in finishing impression back solid phase is lower than the surface energy of the anticorrosive additive material that deposits on substrate surface, wherein impresses the imprinted pattern through transfer printing in the anticorrosive additive material that deposits on described substrate surface.

11. one kind is transferred to the method for substrate with pattern from original impression, may further comprise the steps in imprint process:

-pattern on original impression surface is contacted with polymeric material, described polymeric material comprises one or more cyclic olefine copolymers (COC), to produce a kind of flexible polymer foil that has with the body structure surface of original impression surface opposite pattern;

-free flexible polymer foil from original impression; With

-opposite pattern of flexible polymer foil is pressed into substrate surface, with duplicate at substrate surface impression original impression picture on surface,

Wherein, the surface energy that is heated to the flexible polymer foil of the above temperature of its glass transition temperature is higher than the surface energy of the original impression that applies anti-stick film; And the surface energy of the flexible polymer foil in finishing impression back solid phase is lower than the surface energy of the anticorrosive additive material that deposits on substrate surface, wherein impresses the imprinted pattern through transfer printing in the anticorrosive additive material that deposits on described substrate surface.

12. method as claimed in claim 11, wherein flexible polymer foil have 28 and 40mN/m between surface tension.

13. method as claimed in claim 11, wherein flexible polymer foil have 28 and 37mN/m between surface tension.

14. method as claimed in claim 11, wherein flexible polymer foil have 30 and 35mN/m between surface tension.

15. method as claimed in claim 11, wherein the COC polymeric material is based on the multipolymer of cyclic monomer and ethene.

16. method as claimed in claim 15, wherein the COC polymeric material is based on: 8,9, and 10-trinorbornene-2-alkene (norborene) or 1,2,3,4,4a, 5,8,8a-octahydro-1,4:5, the multipolymer of 8-dimethanonaphthalene (tetracyclododecen) and ethene.

17. method as claimed in claim 11, wherein original impression is made by polymkeric substance, metal, quartz or silicon.

18. method as claimed in claim 11, wherein the anti-sticking layer on original impression has 20mN/m or littler surface tension.

19. method as claimed in claim 11, wherein the anti-sticking layer on original impression has 18mN/m or littler surface tension.

20. method as claimed in claim 11, wherein the original impression surface is provided with the individual layer (SAM) of Automatic Combined as anti-sticking layer.

21. method as claimed in claim 11, wherein the original impression surface be provided with Automatic Combined individual layer (SAM) as anti-sticking layer, it comprises fluorinated alkyl phosphoric acid derivatives, fluorinated alkyl poly-phosphate derivative, PTFE or fluorinated alkyl silane.

22. method as claimed in claim 11, wherein the anticorrosive additive material on the substrate surface has＞surface tension of 40mN/m.

23. method as claimed in claim 11, wherein the anticorrosive additive material on the substrate surface is the material of radiation cross-linkable, and it may further comprise the steps:

-flood anticorrosive additive material by the flexible polymer duplicate with UV light, with crosslinked resist layer.

24. method as claimed in claim 11, wherein flexible polymer foil forms by injection molding, and it may further comprise the steps:

-on first support member, settle original impression;

-leave the first support member certain distance to settle second support member, between the body structure surface of second stayed surface and original impression, have at interval;

-will comprise that the polymeric material of one or more COC is heated to liquid state;

-under pressure liquid COC polymeric material is injected at interval; With

-cured polymer material has flexible polymer foil with original impression picture on surface opposite configuration surface with generation.

25. method as claimed in claim 11, wherein substrate is a semiconductor material.

26. method as claimed in claim 11, wherein flexible polymer foil has the thickness of 50 μ m-1mm.

27. method as claimed in claim 11, wherein flexible polymer foil has the thickness of 75 μ m-250 μ m.

28. method as claimed in claim 11, wherein flexible polymer foil has the glass transition temperature between 100 ℃ and 250 ℃.

Images